Just picked up this '71 B-body 8.75 rear for my charger and when sprayed off found a big ole "BG" on rear and on the front carrier it has orange splashes all over it on top and ps side...almost looks like someone was bored and painted stripes on it. Any ideas on the BG? Thanks.

B...B body
G...'71(F would have been '70 etc.)
an orange dab on the bottom or filler plug would indicate sure grip
various blue and white patches indicated gear ratio and main shaft sizes ,i e. 3.23 gears 489 case or whatever

Thanks for the info! I knew someone here would know. Thanks again.